Treatment fluids based on bicarbonate were originally used in dialysis systems. When these systems, and the monitors for same, were later automated, however, difficulties such as precipitation arose from the use of these bicarbonates. Other treatment fluids were therefore used instead, such as fluids based on acetates. Recently, however, bicarbonate-based liquids have again found favor, and at the same time, the problems which were previously thought to be insurmountable have, in the main, been overcome. However, certain problems still remain with respect to precipitation. Also, the systems in current use must be cleansed at regular intervals. This has been achieved heretofore by rinsing these systems with the aid of a cleansing liquid, such as citric acid.
U.S. Pat. No. 4,728,496 describes a system for disinfection and/or sterilization of systems, such as dialysis monitors. According to this patent, the fluid used for the treatment is recirculated within the part of the system which precedes the dialyzer. As is explained below, this system can, after certain additions, also be used for application of the present invention.
U.S. Pat. No. 4,784,495 describes another system for the control of medical treatments, such as dialysis, in which the treatment fluid to be employed is prepared from a powder-based concentrate, such as sodium bicarbonate. Even in this system, the present invention can also be advantageously applied.
It is therefore an object of the present invention to provide a simple method for cleaning systems of the above-mentioned type.